A lead shot of $1mm$  diameter falls through a long column of glycerine. The variation of its velocity $v$. with distance covered is represented by

Define coefficient of viscosity.

A spherical ball of radius $1 \times 10^{-4} \mathrm{~m}$ and density $10^5$ $\mathrm{kg} / \mathrm{m}^3$ falls freely under gravity through a distance $h$ before entering a tank of water, If after entering in water the velocity of the ball does not change, then the value of $h$ is approximately:

(The coefficient of viscosity of water is $9.8 \times 10^{-6}$ $\left.\mathrm{N} \mathrm{s} / \mathrm{m}^2\right)$

A small metal sphere of radius $a$ is falling with a velocity $v$ through a vertical column of a viscous liquid. If the coefficient of viscosity of the liquid is $\eta $ , then the sphere encounters an opposing force of

The graph between terminal velocity (along $y-axis$ ) and square of radius (along $x-axis$ ) of spherical body of density $\rho $ allowed to fall through a fluid of density $\rho $  is $a$